PO Modification only print the line changed in the pdf embeded in modification email

Hi
We are trying to reove connection sending connected transportation completed for POs.

We archetypal went to SPRO : Materials Management > Purchasing > Messages > Fields applicable to printouts of changes and deselect PO column

We past had to travel to SPRO and add
Materials Management > Purchasing > Messages > Output Control > Message benignant > specify connection benignant for acquisition bid > Maintain Message Types for PO
We person acceptable Program to FM06AEND and FORM regular to CHANGE_FLAG.

It seems to wok but present erstwhile we alteration a enactment (material) successful the PO, alternatively of receiving the full caller PO attached arsenic PDF, the PDF lone contains the enactment changed.

Do you cognize wherever this could travel from ? Or bash you cognize what is the abap programme called to make the PO PDF ?

Thanks